I thought about starting a thread on this but I think it's particularly germane to this one.
Feinstein's mental deterioration seems much more advanced than Biden's. I think that the Democrats would first remove (convince to retire) Feinstein to set precedent, then address the POTUS issue.
https://www.sfchronicle.com/politics/article/dianne-feinstein-senate-17079487.phpColleagues worry Dianne Feinstein is now mentally unfit to serve, citing recent interactions
WASHINGTON — When a California Democrat in Congress recently engaged in an extended conversation with Sen. Dianne Feinstein, they prepared for a rigorous policy discussion like those they’d had with her many times over the last 15 years.
Instead, the lawmaker said, they had to reintroduce themselves to Feinstein multiple times during an interaction that lasted several hours.
Rather than delve into policy, Feinstein, 88, repeated the same small-talk questions, like asking the lawmaker what mattered to voters in their district, the member of Congress said, with no apparent recognition the two had already had a similar conversation.
The episode was so unnerving that the lawmaker — who spoke to The Chronicle on condition they not be identified because of the sensitivity of the topic — began raising concerns with colleagues to see if some kind of intervention to persuade Feinstein to retire was possible. Feinstein’s term runs through the end of 2024. The conversation occurred several weeks before the death of her husband in February.